Table 1.
Antibacterial activity of bulk ZnO and zinc oxide nanoparticles (ZnO NPs) against Salmonella spp., E. coli, and S. aureus at various concentrations. The antibacterial activity was measured by the inhibition zone in millimeters (mm).
| Concentration (µg/mL) | Zone of Inhibition (mm) | |||||
|---|---|---|---|---|---|---|
| Salmonella spp. | E. coli | S. aureus | ||||
| Bulk ZnO | ZnO NPs | Bulk ZnO | ZnO NPs | Bulk ZnO | ZnO NPs | |
| 1000 | ND | 8.00 ± 0.00 d | ND | 8.00 ± 0.00 c | 7.33 ± 0.58 c,y | 11.33 ± 1.15 c,x |
| 2000 | ND | 9.33 ± 0.58 c | ND | 9.00 ± 1.00 b | 7.67 ± 0.58 c,y | 12.00 ± 1.00 c,x |
| 3000 | ND | 10.67 ± 0.58 b | ND | 10.33 ± 0.58 a,b | 8.67 ± 0.58 b,y | 15.00 ± 1.00 b,x |
| 4000 | ND | 12.00 ± 0.00 a | 7.00 ± 1.00 a,y | 11.00 ± 1.00 a,x | 9.67 ± 0.58 a,y | 16.00 ± 1.00 b,x |
| 5000 | ND | 12.33 ± 1.53 a | 8.00 ± 0.00 a,y | 12.00 ± 1.00 a,x | 10.00 ± 1.00 a,y | 19.67 ± 0.58 a,x |
a–d Mean values with different superscripts in the same column corresponding to each type of bacteria are considered statistically different (p < 0.05). x,y Mean value with different superscripts in the same row corresponding to different concentrations of ZnO NPs are considered statistically different (p < 0.05). Values are mean ± SD error of three replicates. ND = No diameter for inhibition zone.